The present invention relates to watercraft, and more particularly to watercraft including a system that measures, controls and monitors the amount of liquid within a ballast tank of the watercraft.
Ballast systems are used in watercraft to control the attitude of the watercraft in the surrounding water. For example, ballast systems generally cause the watercraft to ride higher or lower in the water, displacing less or more surrounding water, respectively. In connection with performance or recreational watercraft used to waterski or wakeboard, rudimentary ballast systems exist to control the attitude of the watercraft, thereby achieving a particular wake behind the watercraft. This is of interest because a wake boarder or a water skier uses the wake created by the watercraft (and directly influenced by the ballast) as a ramp to launch themselves into the air and perform aerial feats.
Conventional ballast systems can be operated to adjust the volume of water in a ballast tank, by either adding or removing water from a ballast tank. The adjustment can compensate for passengers on the watercraft or can provide a desired adjustment to the attitude of the boat to meet a watersport athlete's wake preference behind the watercraft. An example of a recreational watercraft ballast system is shown in FIG. 1. There, the system includes ballast tank 10 and a water level sensor 20. Although not shown, the ballast tank can be filled or drained with fill and drain pumps, controlled by operator on/off switches run through an operating system of the watercraft. The sensor 10 provides feedback on the level of water in the ballast tank.
Ballast systems of watercraft as shown typically include only one water level sensor 20 per ballast tank 10. The sensor 20 usually is a float sensor and/or reed switch sensor having step functions between resistive contacts. Generally, such systems are plagued with inaccuracy where the watercraft is moving or in a dynamic state. Specifically, as shown in FIG. 2, the sensor 20 cannot identify the actual water level in the ballast tank 10 because the water in the tank is sloshing around, while the watercraft is moving, causing the float 21 of the sensor to move. Thus, the water level, in reference to where the sensor 20 and float 21 are located, rises and lowers erratically, based on movement of the watercraft.
As a result, the sensor and ballast system provide erroneous and/or inaccurate readings of the level of the water in the ballast tank, while the watercraft is moving. In turn, many times, the attitude of the watercraft is not adjusted properly, and a desired performance is not achieved. This can be particularly problematic where an operator is attempting to achieve a particular wake for wakeboarding, waterskiing or other recreational water activities. Further, the aforementioned issues are exacerbated where ballast tanks are triangular or of a complex polygonal shape, or where the ballast tanks are flexible membrane bags that are cylindrical or cuboid when filled.